src: use namespace prefix osmo_* for misc utils

Summary of changes:

s/bcd2char/osmo_bcd2char/g
s/char2bcd/osmo_char2bcd/g
s/hexparse/osmo_hexparse/g
s/hexdump/osmo_hexdump/g
s/hexdump_nospc/osmo_hexdump_nospc/g
s/ubit_dump/osmo_ubit_dump/g
s/static_assert/osmo_static_assert/g
diff --git a/openbsc/src/osmo-bsc_nat/bsc_ussd.c b/openbsc/src/osmo-bsc_nat/bsc_ussd.c
index a6fcffc..bbbeead 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_ussd.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_ussd.c
@@ -109,7 +109,7 @@
 	}
 
 	LOGP(DNAT, LOGL_NOTICE, "MSG from USSD: %s proto: %d\n",
-		hexdump(msg->data, msg->len), msg->l2h[0]);
+		osmo_hexdump(msg->data, msg->len), msg->l2h[0]);
 	hh = (struct ipaccess_head *) msg->data;
 
 	if (hh->proto == IPAC_PROTO_IPACCESS) {